1. Field of the Invention
The present invention broadly relates to systems for telephone caller identification, and more particularly, to a system and method to identify a telephone caller by performing voice recognition on the callee identification information spoken by the caller.
2. Description of the Related Art
Telephone communication has seen a phenomenal growth since its inception because of its extreme usefulness in today's world. It is hard, and almost impossible, to conceive a world without telephones. Telephones have almost become an integral part of a civilized society. However, the advances in telephony have brought with them some undesirable consequences. For example, when a called party (or “callee”) does not wish to speak with a particular person or persons, any calls from these calling parties (or “callers”) will be perceived by the callee as a major source of disturbance and annoyance. The callee may not wish to accept a telephone call from a particular caller for a variety of reasons, such as, callee's preoccupation with an important task, callee's desire for privacy, the caller is a telemarketer, etc.
The callee may thus wish to selectively receive a call based on the prior determination of the identity of the caller. In other words, the called party may prefer to determine who the caller is prior to receiving the call. One obvious way to accomplish this is to route all the calls to a human operator who first determines the identity of the caller and then asks the called party (while putting the caller on hold) whether the call is to be accepted or not. If the called party indicates that the caller is an unwanted caller or the caller be connected to an automatic message recording system, the human operator may politely refuse the access to the callee and/or connect the caller to the message recording system. This approach, however, requires presence of a human operator which may not be desirable and cost-effective. Furthermore, some callers may perceive the inquiry by the operator of their names as offensive or rude.
A second approach to pre-screen a caller is to provide the called party with a visual indication of the name of the caller so that the called party can determine whether to accept the call or not. A typical visual indication may be provided by subscribing to the caller name identification service (also known as the ‘calling name service’). However, the calling party may ask the telephone service provider to “block” the transmission of the caller's name to the display apparatus of the called party. In other words, the caller may easily circumvent the identity detection aspect of the calling name service. In such an event, the callee may not be able to avoid or screen the call without first speaking with the caller.
In the third approach, an automatic caller screening device is employed to identify and screen the caller (if necessary) prior to forwarding the call to the called party. FIG. 1 illustrates how a prior art automatic digital call assistant 10 functions as a caller-screening interface between a calling party 12 and a called party 14. Such automatic call-screening devices may typically be employed in an organization where it may not be desirable to allow unfettered access by the outside callers to the called parties (i.e., the employees of the organization). Initially, the caller 12 dials the phone number of the called party 14 (step 15). The call assistant unit 10 first receives the call placed by the caller and automatically enters into an off-hook condition. This establishes a telephone communication link between the caller 12 and the digital call assistant 10.
Thereafter, at step 16, the call assistant 10 generates, in a synthesized voice, a greeting and/or an announcement (e.g., “Thank you for calling XYZ corporation. This is an automatic answering service for Mr. ABC.”) followed by a query asking the caller to speak the caller's name (e.g., “Please tell me who you are,” or “Please clearly speak your name.”). In response to the name query by the call assistant unit 10 for the called party 14, the calling party 12 may either hang up or provide the caller's name at step 17. The spoken words constituting the caller's name are thus received by the digital call assistant 10 at step 17. To prevent the caller from disconnecting, the call assistant 10 may optionally play a second announcement (e.g., “Please hold on while I connect you to Mr. ABC,” or “You are being connected to Mr. ABC. Please do not disconnect,” or, simply, “Please hold for a moment.”) at step 18.
In the meantime (i.e., while the caller is on hold), at step 19, the digital call assistant 10 creates a digital sound file (also referred to as a ‘digital audio file’) from the spoken syllables received from the caller. The digital audio file may be a wave (“.WAV”) file. The .WAV file is then converted into a digital ASCII (American Standard Code for Information Interchange) text file at step 20. The ASCII text file is thus generated based on speech recognition of the speech uttered by the caller. Assuming that the caller's name is John Doe, the speech-to-text conversion at step 20 results in the ASCII text file sequentially containing (in hexadecimal notation) ASCII codes 4A, 4F, 48, 4E for letters “J”, “O”, “H” and “N” respectively; ASCII code 20 for the ‘blank’ between the words “John” and “Doe”; and ASCII codes 44, 4F and 45 for letter “D”, “O” and “E” respectively. Thus, the caller's name is represented within the call assistant 10 as a string of binary 1's and 0's.
The call assistant 10 then queries, at step 21, a portion of a database that is associated with the called party to determine whether the called party has placed any restriction on the calls from that specific caller. The ASCII file containing the name of the caller is compared with other ASCII files within the database to find a matching name, i.e., to determine whether the caller is one of the proscribed callers. Here, Mr. ABC may identify (in the database) that calls from caller John Doe need not be forwarded to Mr. ABC. Alternatively, Mr. ABC may not put any restriction on the calls from caller John Doe. Thus, depending on the information in the database, the digital call assistant 10 may generate appropriate announcement at step 22. If the caller 12 is allowed to be connected to the called party 14, the announcement may state so (e.g., “You are being connected to Mr. ABC. Please continue to hold.”). On the other hand, if the caller 12 is not allowed to directly call the callee 14, the announcement may indicate that the called party 14 is unavailable to answer the phone (e.g., “Mr. ABC is not in his office at this time. Please enter “0” to access his voice mail-box,” or, simply, “Sorry, Mr. ABC is not in his office. Goodbye.”). If the caller 12 is allowed to proceed with the call, the call assistant 10 sets up a call to the called party 14 at step 23. This directly connects the calling party 12 and the called party 14 and a telephone conversation between them proceeds at step 24 once the called party 14 answers the call.
Even the speech recognition-based automated caller-screening approach described hereinbefore with reference to FIG. 1 has certain undesirable attributes to it. The initial inquiry of the caller's name may not be received favorably by a number of callers. Such an inquiry may instead be perceived as unduly intrusive and as requiring information about caller's personal identity in an unnatural way and at a time when it may be too premature and awkward to ask the caller's name. Furthermore, if a caller always gets an announcement that the called party is unavailable to take the phone call after every interaction with the digital call assistant (including caller's self-identification every time the caller interacts with the digital call assistant), the caller may start suspecting that the called party is screening the caller based on the self-identification information provided by the caller. Such a negative impression by the caller may not be desirable, especially when there is a professional relationship between the caller and the callee.
It is therefore desirable to automatically screen a caller without asking the caller to identify himself/herself. It is also desirable that the screening of the caller takes place in a manner that the caller perceives as a more natural way of telephone communication.